The present invention relates to a bus relay apparatus and, more particularly, to a bus relay apparatus for use in a multi data communication processing system, for dividing data communication processors into several groups and performing a polling operation in units of groups, thereby performing communication between relay apparatuses.
A conventional relay apparatus of this type has input and output ports and relays an address received at the input port to the output port. In this case, the direction of a bus is determined by a signal line and independent from a polling signal.
In the above conventional relay apparatus, since direction control of a signal line is performed independently of a polling signal, buses must be looped.